There is known a device for expanding profile pipes in their installation in wells, comprising a conical housing with a central channel, connecting threads and multi-step recesses in a wall, in which rollers with spherical surface are installed and arranged uniformly on axes along circumference of the housing. And the rollers in recesses are mounted perpendicular to longitudinal geometric axis of the housing, and in between them the rams with spherical surface are mounted, where rams of each subsequent stage are placed under the rollers of the previous one (Patent of Russian Federation No 2194841, E21B 29, October 2002).
A drawback of the known device is a low quality of profile pipes expanding, since profile of threaded connections after expanding by each section of the device takes a triangular sectional view. As a result, loss of sealing of threaded connections occurs.
The most close to the invention by technical essence is a device for expanding profile pipes in their installation in wells, comprising a housing with a central channel and three mandrel components, one of which is made in the form of rams, fastened in inclined slots of the housing and spring-loaded away from their extension into working position (Patent of Russian Federation No 2154148, E21B 29, October 2000).
Main drawbacks of this device are low serviceability and reliability in its operation in the open borehole under clay mud presence in it and possible sloughing of rocks, which result in sticking and jamming of mandrel components, especially in the upper part of the device.